Concentrating table



A\ l& 31, 1937. G. w. GILBRE TH 2,091, CONCENTRATING TABLE 2 Sheets-Sheet 1 Filed March 2, 1936 z. m I I INVENTOR ATTORNEY A I I I G. W. GILBRETH CONCENTRATING TABLE Filed March 2,

& lNVENi'OR 4 G. W Giljoretlz BY E K Q ATTORNEY for which it is designed. I

' table.

hanced and the efliciency of the table is Patented Aug. 31, 1937 '1 UNITED STATES PATENT OFFICE 6 Claims.

This invention relates to concentrators of the shaker table type such as are used in placer mining operations. vention is to provide a concentrator table of this type provided with a values-catching surface and With a bafile and riflle arrangement such that an automatic suctional action is induced by the shaking of the table and the movement of the material along the same, which gives a very efiicient concentrating action. 7

Another object is to construct and mount, the portions of the table together so that it is a very easy matter to clean the same out for the recovery of the concentrates thereon.

A further object is to provide a means whereby the material will move in. a zigzag path as it travels from end to end of the table, and if any of the particles of such materials are of relatively large size, they will be broken up as they travel. The concentrating action is thus greatly enhigh.

A further object of the invention is to produce a simple and inexpensive device and yet. one which will be exceedingly effective for the purpose These objects I accomplish by means of such structure and relative arrangement of parts as will fully appear by a perusal of the following Fig. 2 is a top plan view of the concentrator Fig. 3 is an enlarged fragmentary longitudinal section of the same. .4

Figs. 4, 5, and 6 are fragmentary cross sections of the table taken on the lines 4-4, 5-5, and 6-6 respectively of Figure 3.

Referring now more particularly to the characters of reference on the drawings, my improved concentrator table comprises a rectangular, relatively deep and long pan I, open at one end, and into which the gravel or other material is fed adjacent its closed end from a chute 2 or the like. The pan is removably supported on the frame 3 of angle iron, etc., being held against undesired movement relative to the frame .by a releasable hook bolt connection 4- or similar means.

The frame is supported on a downward slope toward one end so that the open end of the pan is-at its lowest point from a fixed base which The principal object of my invery includes beams 5 under the sides of the frames 3v and mounted for vertical adjustment toward, one end to alter their slope. Boxes 6 are secured on the beams in longitudinally spaced relation and slidable therein are rods 1 or the like, having upstanding extensions 8 at one end secured to the 5 frame 3 as shown in Figure ,1. The frame and pan are thus mounted for straight lengthwise movement in a plane at an angle to a. horizontal plane.

Such movement is imparted to the frame in 1 any suitable manner such as by a drive shaft 9, having eccentrics ll] thereon which are connected by arms H to the frame 3 intermediate its ends.

The main feature of my invention however, resides in the construction and-arrangement of the material engaging and concentrating elements in the pan-which will now be described. Removably; disposed in' the pan and resting on the bottom thereof is a false floor I2. This is of resilient'sheet metal and extends from end to end of the pan, but is spaced from the sides somewhat.- This floor is bent upwardly at intervals of its length to form what may be termed combination spring hinge and rifiie elements I3 of substantially viii-shaped form in section, and pinched-in intermediate their top and bottom. These rifiles extend transversely of the floor for its full width, but at their ends are beveled off at an angle of approximately 45 for their full height as indicated at M in Figure 5.

The false floor including the riffle elements I3 arecov ered with a layer l5 of porous material such as carpeting or the like. This layer extends to the side edges of the pan as shown in Figures 4, 5,1 and 6, and it contacts with 1711611001 throughout its area except where the riffles are pinched-in, where small-spaces are formed between the riiiles and carpeting as shown in Figure 3. .40

Superimposed on the carpet are transverse,- evenly spaced bafiies l6 spaced evenly between the riflles. These are preferably of inverted L- shaped form with their flanges facing toward the low end of the pan as shown. in Figure 3. These baflles extend between and are rigidly secured to side plates ll which removably fit in the pan in close relationship to the sides thereof; the bafiles and side plates thus forming a single unit removable from the pan. The side plates are connected at intervals by crossbars ill on top which are disposed slightly above and overhangflanges l9 which extend along the top edges of thepan. Suitable releasable. clamping bolts ZIJ'thrOugh the flanges and crossbars hold the,

baffles and side plates against upward displacement.

The plates I! are arranged so that when the bolts are tightened down, inturned flanges 2| 5 along the lower edges of the plates firmly engage the carpet along its side edges and clamp the same against the bottom of the pan, Also the baffles are arranged so that the lower edges of the alternate ones are on a lower level thanthe remainder, so that they likewise engage the adjacent portion of the carpet and clamp the same and the false floor against the bottom of the pan at corresponding points. The lower edges of the other baffles, however, normally clear the carpet somewhat as plainly shown in Figures 3" and 6;

The false floor between adjacent bafiles is norcmally curved upwardly or raised. slightly in, the longitudinal direction as shown at 22in Figure 3.- These raises are preferably of shallow arch;- like form, with the riffle and hinge elements l3 at the highest point ofthe arch. Thefalse bottombeing of resilient metal, it will tend to hold its curved form, but can yield downwardly for the purpose which will be seen.

Secured onthe back side of the bafiles are deflectors 23 which are of wedge-shaped form in plan. Theseextend in' converging relationship from the side plates 11 to the back side of the bafilesandterminateadjacent the center of the 30 length thereof; being arranged in opposed or staggered relation on alternate baffles as shown in Figure 2'. Also projecting from the said back side of the baffles at the top and also from the corresponding portions of the'deflectors are hori- 35 zontally extending triangular shaped teeth or agitators 24 which face toward the high or feed-in endof= the pan.

Inoperation, as the material to be concentrated isfed into the pan at its upper end; it tends to 4 =move toward the lower open end-of the pan due to the slopeof the latter. The-longitudinal agitation orshake ofthe table'causes-such material to be'intermittently thrown-againstthe back side of the baflles. This action not only causes the 5 teeth 24 to break up any large pieces of such material as they-tend to move overt'he top of the baffles but the angularly' disposed deflectors 23 causethe material striking the-same to be shifted laterally somewhat. Since the deflectors- 50 are disposed in alternately-staggered relation; the' material travelling from one endto the otherof the table follows a zigzag path as indicated by the-dotted line in Figure 2; A very efiicient values separating action effective over the full 5 width and length of the table is-thusobtained andany tendency for the material to-pack on the'table is avoided.

Also with the intermittent pounding of the mass of material on-the carpet between the baffles- 0 had as a result of the table shaking and bafllestriking action, theresilient falsefloor is caused to have'a vertical bellows-like movement along its different upwardly curved portions 22'; This movement of the floor creates asuctional effect 6 tending to draw air through'the areas of the carpet across theopen ends-of theriffles l3-as well as along the same where the carpet is spaced-from the rifiles; As a result, the values in the'material and striking the riffles as thematerial is being 7 Washed along the carpet, is drawn into and held in the pores of the carpet adjacent said rifiies.

Whenit is desired to-make acleanup it is obviously an easy matter to remove the-baffle units by releasing the bolts 20- and withdrawingthe 75 carpet with itsprecious content. It may here be noted that since the side edges of the false floor are spaced from the sides of the pan, said floor is not pinched or clamped by the plate flanges 2| so that said floor is free for the desired and necessary vertical movement under the clamped carpet.

From the foregoing description it will be readily seen that I have produced such a device as substantially fulfills the objects of the invention as set forth herein.

While this specification sets forth in detail the present and preferred construction of the device, still: in practice such deviations from such detail may be resorted to as do not form a departure from the spirit of the invention, as defined by the appended claims.

Having. thus described my invention, what I claim as new and useful and desire to secure by Letters Patent is:

1. A concentrator table comprising a relatively long pan open at one end, means supporting the pan for longitudinal shaking movement andat a downwardslope to its open end, means to-feed material into the upper end of the pan, means to shake the pan whereby the-material will tend to move toward the lower open end of the pan, a removable-values collecting carpet covering the area of the bottom of the pan, means releasably clamping the side edges of thecarpet against the bottom of the pan, transverse rigid bafiles in the panupstanding from and engaging the carpet at longitudinally spaced intervals, aresilient metal false floor under the carpet normally having aflat, arch likeraise between adjacent baflles; the floor being bent upwardly at the peak ofeach raise to form hollow transverse riffles ofsubstantially A-shaped form.

2. A structure as in claim 1, in which the ends of the rifiies are cut awayon an inward bevel to the top; the carpet covering the open beveledendsof the rifiles and following substantially the exterior contour of the riflies lengthwise ofthe same.

3. A concentrator table comprising arelatively longpan openat one end, means supporting the nally spaced intervals and extending from sideto side of the-pan, aresilientfalse floor under the carpet normally holding the same yieldably raised between the baflles, andmeans formed with said floor to cause a suctional action to be had through the carpet between the battles with the shaking ofthepan and the movement of the material in the pan induced by such shaking.

4. A concentrator table comprising a relatively long pan openat one end, means supporting the pan for longitudinal shaking movement and at adownward slope to its open end, means to feed material into the upper end of the pan,-means to shake the pan whereby the material willtendto move toward the lower open'end of the pan, a removable values collecting carpet covering the areaofthe bottom of the pan, and transverse upstanding bafiles disposed in the pan at longitudinally spaced intervals and extending fromside to side of the pan and to adjacent thecarpet, rifil'es extending transversely of the pan under the-- carpet and holding the same raised at points intermediate the baffles, said riffles being hollow and terminating short of the sides of the pan and being open at their ends, the carpet extending over and covering said open ends.

5. A concentrator table comprising a relatively long pan open at one end, means supporting the pan for longitudinal shaking movement and at a downward slope to its open end, means to feed material intothe upper end of the pan, values collecting means in the pan, longitudinally spaced transverse baflies in the pan, said baffles being relatively short in height, means to shake the pan to cause the material to tend to move toward the lower end of the pan and so that some of such material will be thrown against the baffles, and spaced teeth projecting in the direction of the upper end of the pan from the adjacent face of the baflles whereby to tend to act on and split the material thrown against the baffles.

6. A concentrator table comprising a relatively long pan open at one end, means supporting the pan for longitudinal shaking movement and at a downward slope to its open end, means to feed material into the upper end of the pan, means to shake the pan whereby the material will tend to move toward the lower open end of the pan, a removable values collecting carpet covering the area of the bottom of the pan, transverse rigid baffles upstanding from the carpet at longitudinally spaced intervals and extending from side to side of the pan, a resilient false floor under the carpet normally holding the same yieldably raised between the baffles, and means formed. with said floor to cause a suctional action to be had through the carpet between the baflles with the shaking of the pan and the movement of the material in the pan induced by such shaking; the lower edge of alternate baffles terminating clear of the carpet while the remaining baffles clamp the carpet against the false floor. v

GEORGE W. GILBRETH. 

